My tail lights are not working
 

i have headlights, turn signals work, brake lights work, hazards work , dome lights dash, check fuses checked lisense plate bulbs , i installed an EL Glow light gauges and wired it to the light swith blue and red wire which is what it called for and grounded the black wire to a good ground source, had tail lights then , got pulled over by the police and he told me i had no tail lights , hard way to find out but he didnt ticket me , any help would be great, Thanks